Heterodyne frequency converter



Oct. 30, 1951 L. RIEBMAN HETERODYNE FREQUENCY CONVERTER Filed Jan. 15, 1946 grwmq to b LEON RIEBMAN Patented Oct. 30, 1951 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 3 Claims.

This invention relates to radio frequency components and is particularly directed to a novel arrangement of components for greater compactness and simpler coupling.

The invention provides means for inserting a lighthouse type tube longitudinally in a coaxial line and another lighthouse tube transversely in the coaxial line. The tubes can be 50 arranged that the plate of an amplifier can be coupled to the grid of another amplifier or to a mixer through the coaxial line Without the use of wire connections. The losses due to ohmic resistance are thereby minimized. Also, by this arrangement, an amplifier or mixer unit can be made to occupy less space.

It is an object of the invention to provide a means of inserting a tube longitudinally and another tube transversely in a coaxial line.

It is another object of the invention to provide a more compact amplifier or mixer unit at radio frequencies.

It is another object of the invention to couple the plate of one lighthouse type tube to the grid of another by suitable insertion of one tube longitudinally and the other transversely in a coaxial line.

The invention will be further understood with reference to the exemplary embodiment shown in the drawing in which:

Fig. 1 shows, partially in longitudinal cross section and partially in schematic diagram, an exemplary arrangement of R.F. components in a mixer or converter; and

Fig. 2 is a partial cross sectional view of Fig. 1 taken on the line 2-2 of Fig. 1.

The converter unit of Fig. 1 comprises an amplifier tube I I, a mixer I2, and an oscillator I3. These tubes are of the type having annular rings for coupling the tube elements to circuit elements.

Coaxial lines I4 and I5 each have an outer conductor of a rectangular cross section and are joined together by having a common side 35. Lines I4 and I5 also have coaxially disposed therein tubular inner conductors I I and 38 respectively.

Oscillator tube I3 is inserted longitudinally in end 36 of coaxial line I5 and securelypositioned therein by known means. The grid element of tube I3 is connected through its annular ring by cylinder M and the fingered annular contact ring 40 to the outer conductor of coaxial line I5. The plate element of tube I3 is connected by means of a cup shaped fingered contact member 39 to the inner conductor 38 of coaxial line I5.

tube I2 to the line I4.

Amplifier tube II is inserted longitudinally in end 37 of coaxial lin'e I4 and securely positioned therein. Plate ring I6 of tube II is coupled for R. F. to the outside of inner conductor I! of coaxial line I4 through fingers I8 and conductors I9 and capacitively across insulator 20. Grid ring 23 is connected, such as shown at 42, to the inside wall of outer conductor 25 of line I4.

Mixer tube I2 is inserted transversely Within coaxial line I4 having provisions therein for receiving the tube such as shown at 43. The position of mixer tube I2 in the line with respect to amplifier tube II is chosen to permit maximum power transfer to the mixer I2 from amplifier I I.

- Snorting bar 22 is made adjustable to obtain a better match of the input impedance of mixer Grid line 2I of mixer tube I2 is coupled to the inner conductor I! through connector 44. Cathode ring 2I of mixer tube I2 is coupled to the inner conductor I! through connector 44. Cathode ring 24 is connected to the inside wall of outer conductor 25 of line I4 at 43. The amplified voltage at plate I6 of tube II is coupled directly to grid 2| ofthe mixer tube I2 through the coaxial line I4.

In the operation of the circuit, the output from the local oscillator I3 is coupled through an iris 26, formed in the common wall member 35, to the mixer I2, and the intermediate frequency output from the mixer is developed across transformer 21.

The transverse cross section of coaxial line I4 in Fig. 2 further illustrates the connections for tube I2. As already noted, grid ring 2| is connected to the outside of the inner conductor I1, and cathode ring 24 is connected to the inside of outer conductor 25.

Although the arrangement of R.-F. components herein described illustrates the coupling of an amplifier to a mixer, it could be used as well to couple an amplifier to another amplifier.

Although I have shown only certain and specific embodiments of the present invention, it is to be expressly understood that many modifications are possible thereof without departing from the true spirit of the invention.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is:

1. In combination a, section of coaxial line including inner and outer conductors, a first vacuum tube having at least cathode, grid and plate elements with annular contact rings attached thereto, means for longitudinally supporting said vacuum tube in one end of said coaxial line, means for capacitively coupling said plate to the inner conductor and means for connecting said grid to the outer conductor of said line; a second vacuiunltube. also having at,least a cathode,-

grid andplate elements with annular rings at: tached thereto, means for transversely supporting said second vacuum tube in said line, means;

connecting the grid of said second vacuum tube to the inner conductor and the cath ode of said: second vacuum tube to the outerwcgndnctor oft,-

said coaxial line and output means connected to the plate of said second vacuumv tubetforsreceivm ing an output therefrom.

2. In combination a first and second section of coaxial line each including inner and outer conductors, the outer conductor of eachsectionhaving a rectangular cross-section the outer conductorsof said line sections being disposed in contiguo'us relation with a vcommon side joining the. use sections, a first and second vacuumtube, means for longitudinally supporting each ofsaid tubes in one .e'nd'of said first and second sections of .coaxialf line, a third. vacuum.tube,,means for transversely supporting the same in said second section of 'coaxialline in direct contact with the inner .andouth conductors thereof, means for capacitively.couplingone electrode of said secondvacuum tube tothe innerconductor of said sec.

ond. section of coaxial line for coupling the output "therefromto said third vacuu m tube and an iris in the common side ofthe two linesior cou pling the output from jsaidl first vacuum -tube to;

the, vacuum tube.

3131].? first coaxial line section, means for capacitively coupling theplate of said tube to the inner conductor of 'sa-id' first line section and means for connecting the grid of said tube to the outer conductor of said first line section, a mixer tube :also-hav-ingat leastcathode, plate and grid electrodeswith annular contacts attached thereto, means for transversely supporting said mixer tube in said first coaxial line section, means connecting the grid of said mixer tube to the inner conductor of said first line section, an oscillator tube longitudinally supported in the second line-section, and an-iris coupling-slot, formed in the common sidewhich joins said first and secondline sections for coupling the oscillator signalto the mixer.

LEON RIEBMANU REFEBEN CES; CITED 1 The following references are of recordin the file of thispatent:

NITEDBTATESJPATENTSJ Number Name Date Turner Feb. 18,-. 1947 

